Bioassay for volatile low molecular weight insecticides and methods of use

Abstract

The subject invention pertains to materials and methods for screening of volatile insecticides for activity against pests, such as those that pose a threat to public health (e.g., dipterans such as flies and mosquitoes). One aspect of the invention pertains to an apparatus and bioassay for screening volatile compounds for activity against pests. The subject invention also concerns methods of using volatile compounds as insecticides against pests that pose a threat to public health, such as flies and mosquitoes. The compounds used in the present methods can be formulated for use as an insecticide. The subject invention also concerns volatile compounds formulated for use as insecticides against pests that pose a threat to public health, such as flies and mosquitoes.

1 . A bioassay for screening volatile compounds for activity to kill a pest, said method comprising: 
 a) providing one or more pests in a first container that permits gas exchange;    b) providing said first container within a second container that comprises a liquid absorbent material, wherein said liquid absorbent material is absorbed with a compound or mixture of compounds to be screened for activity;    c) sealing said second container wherein said one or more pests are exposed to said compound or mixture of compounds; and    d) determining the mortality of said one or more pests exposed to said compound or mixture of compounds.    
   
   
       2 . The bioassay according to  claim 1 , wherein said pest is an insect.  
   
   
       3 . The bioassay according to  claim 2 , wherein said one or more insect is a fly.  
   
   
       4 . The bioassay according to  claim 3 , wherein said fly is a  Drosophila  species.  
   
   
       5 . The bioassay according to  claim 1 , wherein said compound or mixture of compounds is provided in solution at a concentration of between about 10 μg/μl to about 1000 μg/μl.  
   
   
       6 . The bioassay according to  claim 1 , wherein said compound or mixture of compounds is provided in a solvent selected from the group consisting of acetone, ethanol, methanol, methyl cellosolve, dimethyl sulfoxide (DMSO), and hexane.  
   
   
       7 . The bioassay according to  claim 1 , wherein said one or more pests are exposed to said compound or mixture of compounds for between about 12 hours to about 48 hours.  
   
   
       8 . The bioassay according to  claim 1 , wherein a food substance is provided within said first container.  
   
   
       9 . The bioassay according to  claim 1 , wherein an inhibitor of a cytochrome P450 enzyme is also provided in said second container.  
   
   
       10 . The bioassay according to  claim 9 , wherein said inhibitor is piperonyl butoxide (PBO).  
   
   
       11 . The bioassay according to  claim 1 , wherein an inhibitor of an esterase enzyme is also provided in said second container.  
   
   
       12 . The bioassay according to  claim 11 , wherein said inhibitor is SSS-tributyl-phosphorotrithioate (DEF).  
   
   
       13 . A method for killing a pest, said method comprising exposing or contacting a pest with an effective amount of a volatile compound identified using a method according to  claim 1 .  
   
   
       14 . The method according to  claim 13 , wherein said pest is an insect.  
   
   
       15 . The method according to  claim 14 , wherein said insect is a fly.  
   
   
       16 . The method according to  claim 15 , wherein said fly is a  Drosophila  species.  
   
   
       17 . The method according to  claim 13 , wherein said volatile compound is formulated as a fumigant.  
   
   
       18 . The method according to  claim 13 , wherein said volatile compound is in undiluted form.  
   
   
       19 . The method according to  claim 13 , wherein said volatile compound is mixed with or provided with an inert gas.  
   
   
       20 . The method according to  claim 13 , wherein said volatile compound is provided in liquid form.  
   
   
       21 . The method according to  claim 13 , wherein said insect is  Aedes  spp.,  Anopheles  spp.,  Culex  spp. (including  Culex nigripalpus ),  Drosophila melanogaster, Musca  spp. (including  Musca domestica ),  Fannia  spp.,  Calliphora erythrocephala, Lucilia  spp.,  Chrysomyia  spp.,  Cuterebra  spp.,  Gastrophilus  spp.,  Hyppobosca  spp.,  Stomoxys  spp.,  Oestrus  spp.,  Hypoderma  spp.,  Tabanus  spp.,  Tannia  spp.,  Bibio  spp. (including  Bibio hortulanus ),  Oscinella frit, Phorbia  spp.,  Pegomyia hyoscyami, Ceratitus capitata, Dacus oleae , or  Tipula paludosa.    
   
   
       22 . The method according to  claim 13 , wherein said compound is menthofuran, benzothiophene, dihydrobenzofuran, coumaran, 9,9-difluoro-4-methyl-7-oxabicyclo[4.3.0]non-3-ene, 4-methyl-7-oxabicyclo[4.3.0]non-1(6),3-diene, dimethyl-coumarone, indole, formic acid, methyl formate, ethyl formate, propyl formate, butyl formate, hexyl formate, heptyl formate, t-butyl formate, ethylene glycol di-formate, 1,2-propylene glycol diformate, 1,3-propylene glycol diformate, 1,4-propylene glycol diformate, cyclopentyl formate, methyl acetate, ethyl acetate, propyl acetate, n-butyl acetate, pentyl acetate, hexyl acetate, iso-propyl acetate, t-butyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, methyl butyrate, ethyl butyrate, propyl butyrate, methyl valerate, or ethyl valerate, or any combination of said compounds.  
   
   
       23 . The method according to  claim 13 , wherein said volatile compound is formulated with an inhibitor of a cytochrome P450 enzyme.  
   
   
       24 . The method according to  claim 23 , wherein said inhibitor is piperonyl butoxide (PBO).  
   
   
       25 . The method according to  claim 13 , wherein said volatile compound is formulated with an inhibitor of an esterase enzyme.  
   
   
       26 . The method according to  claim 25 , wherein said inhibitor is SSS-tributyl-phosphorotrithioate (DEF).  
   
   
       27 . A pesticidal formulation, wherein said formulation comprises a volatile compound identified using a method according to  claim 1 .  
   
   
       28 . The pesticidal formulation according to  claim 27 , wherein said compound is menthofuran, benzothiophene, dihydrobenzofuran, coumaran, 9,9-difluoro-4-methyl-7-oxabicyclo[4.3.0]non-3-ene, 4-methyl-7-oxabicyclo[4.3.0]non-1(6),3-diene, dimethyl-coumarone, indole, formic acid, methyl formate, ethyl formate, propyl formate, butyl formate, hexyl formate, heptyl formate, t-butyl formate, ethylene glycol di-formate, 1,2-propylene glycol diformate, 1,3-propylene glycol diformate, 1,4-propylene glycol diformate, cyclopentyl formate, methyl acetate, ethyl acetate, propyl acetate, n-butyl acetate, pentyl acetate, hexyl acetate, iso-propyl acetate, t-butyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, methyl butyrate, ethyl butyrate, propyl butyrate, methyl valerate, or ethyl valerate, or any combination of said compounds.  
   
   
       29 . The pesticidal formulation according to  claim 27 , wherein said formulation comprises an inhibitor of a cytochrome P450 enzyme.  
   
   
       30 . The pesticidal formulation according to  claim 29 , wherein said inhibitor is piperonyl butoxide (PBO).  
   
   
       31 . The pesticidal formulation according to  claim 27 , wherein said formulation comprises an inhibitor of an esterase enzyme.  
   
   
       32 . The pesticidal formulation according to  claim 31 , wherein said inhibitor is SSS-tributyl-phosphorotrithioate (DEF).  
   
   
       33 . The pesticidal formulation according to  claim 27 , wherein said pesticidal formulation is formulated as a fumigant.  
   
   
       34 . The pesticidal formulation according to  claim 27 , wherein said volatile compound is in undiluted form.  
   
   
       35 . The pesticidal formulation according to  claim 27 , wherein said volatile compound is mixed with or provided with an inert gas.  
   
   
       36 . The pesticidal formulation according to  claim 27 , wherein said volatile compound is provided in liquid form.  
   
   
       37 . An apparatus for conducting a bioassay for screening volatile compounds for activity against pests, comprising: 
 a) a first container for containing one or more pests, wherein said first container permits gas exchange; and    b) a second container that can contain said first container and that can contain a liquid absorbent material, wherein said second container is releasably sealable.    
   
   
       38 . The apparatus according to  claim 37 , wherein said first container comprises a food substance for said one or more pests.  
   
   
       39 . The apparatus according to  claim 37 , wherein said liquid absorbent material is absorbed with a test compound.  
   
   
       40 . The apparatus according to  claim 39 , wherein said test compound is provided in a solvent that exhibits little or no toxicity to said one or more pests.  
   
   
       41 . The apparatus according to  claim 40 , wherein said solvent is acetone, ethanol, methanol, methyl cellosolve, DMSO, or hexane.  
   
   
       42 . The apparatus according to  claim 37 , wherein said first container has at least one open end comprising a material that prevents said one or more pests from escaping said first container and permits gas exchange with said second container.